Breath tests in Western Australia: Examining the economic dividends and effectiveness of general deterrence.

In this paper, we examine the relationship between traffic enforcement (in the form of roadside breath testing for alcohol) and traffic outcomes (alcohol-related traffic crashes) to identify an optimal point of traffic enforcement. In Western Australia (WA), Police are authorised to stop any driver and measure their blood alcohol concentration via a sample of their breath. Using a metric employed by Ferris et al.